Morphology of Sf9 Cells

The Sf9 insect cell line is a clonal isolate derived from the parental Spodoptera frugiperda cell line IPLB-Sf-21-AE, and it is a suitable host for expression of recombinant proteins from baculovirus expression systems (e.g., Invitrogen’s Bac-to-Bac® and Bac-N-Blue™ Expression Systems). Although insect cells have been historically cultured in stationary systems utilizing T-flasks and serum-supplemented basal medium, insect cells are generally not anchorage dependent and can easily be maintained in suspension culture.

Healthy Sf9 Cell Morphology

The images below show the morphology of healthy Sf9 insect cells in suspension and adherent cultures. Sf9 cells attach firmly to surfaces, and their small, regular size makes them exceptional for the formation of monolayers and plaques.

Figure 3.5: Phase contrast images of healthy Sf9 insect cells grown in suspension. The culture was started in a shake flask at a seeding density of 3 × 105 viable cells/mL in Sf-900 II SFM medium and it was maintained in a 28°C, non-humidified, ambient air-regulated incubator. The images were obtained using 10X and 20X objectives (panels A and B, respectively) 3 days after seeding.

Figure 3.6: Phase contrast images of healthy Sf9 insect cells grown as an adherent monolayer in Sf900 II SFM medium. The cells were plated at a seeding density of 5 × 104 viable cells/cm2 in a T-25 flask and grown as monolayers in a 28°C, non-humidified, ambient air-regulated incubator. The images were obtained using 10X and 20X objectives (panels A and B, respectively) 3 days after seeding.